Dear friends,
THANK YOU ALL FOR YOUR ANSWERS AND ESSPECIALLY Daniel Lichtblau. I managed with your help to fit multiple data to multiple equations simultaneously. Thanks again.
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I have 6 parameters a=7.6; m1= 10; m2=9; d=0.1; of which f1 = 1.64 and f2= 1.72; depend on m1= 10; m2=9; so that for all m1>0&&m2>0 follows:
f1(m1,m2) and f2(m1,m2)
I first determined all six parameters and then replaced f1 and f2 with m1 and m2 by using the command InterpolatingPolynomial in the following way.
FullSimplify[Solve[InterpolatingPolynomial[{(m1/m2)^2, f1}, x1] == 0, f1]
FullSimplify[Solve[InterpolatingPolynomial[{(m1/m2)^2, f2}, x2] == 0, f2]
The disadvantage of this method is that new parameters x1 and x2 will be generated.
Is there a more intelligent way to circumvent this problem ?